Lately I've heard a lot of people talking about what they're not going to do. I'm dead tired, I don't have time for that. You don't know what I've gone through this week, I'm not doing that. I'm so busy, I can't do that. That's not my job. I'm not getting paid enough to do x,y,z. I've been here for x years, they're crazy if they think I'm going to do that.
There's no reason to beat around the bush - if you say these things with any frequency you're completely full of shit. There are far busier and more important people who accomplish more in a day than most of us get done in a week. These people aren't necessarily more gifted or talented, they just focus on doing what they need to do, no matter what.
Working smart is a necessity, but even that entails working. We are living in the greatest time to be alive and most of us are far to casual about doing what we need to do. The sad part is that whenever you remind a negativity-prone person of this, excuses start flying back at you.
Don't worry about doing too much or overworking yourself - 99% of us go from day to day without even coming close to scratching the surface of our full potential. Instead of worrying about what isn't your job, think of what you can do to make your workplace, home, and relationships better. It will be uncomfortable at first, but it just might take you where you want to go.